Splash lubricated air compressor



Aug. 20, 1940.

c. c. FARMER 2,211,889

SPLASH LUBRICATED AIR COMPRESSOR Filed Sept. 22, 1938 2 Sheets-Sheet l I Z Li,

SFi gZ INVENTOR CLYDE C. FAHMEH ATTORNEY Aug. 20, 1940.

c. c. FARMER 2,211,889

SPLASH LUBRICATED AIR COMPRESSOR Filed Sept. 22, 1938 Fig.4.

2 Sheets-Sheet 2 INVENTOR CLYDE C. FARMEH ATTORNEY Patented Aug. 20, 194-0 UNETED sr'rEs:

, Fries 3 Claims. (01. 184-6)- This invention relates tofluid compressors, and

more particularly to a{ compressor of the class involving splash lubricated pistons and crankshaft. I g

5 In air compressors of relatively small capacity,

such asthose designed for use inautomotive or industrial service, it is desirable to provide a simple and inexpensive lubricating system of the splash type embodying means for maintaining a constant supply of oil within the paths of the usual oil dippers, which supply is not impaired by ordinary tilting of the compressor, or when less than the normalquantity of oil is contained in the crankcase. During op'erationof such a com- 7 pressor havingsplash' lubrication, the crankcase chamber usually contains more or less oil vapor,

which might be expelled therefrom with air ad-' mitted by way of leaking piston rings or otherwise trapped in the chamber and somewhat compressed upon downward suction strokes of the piston. For this reason the crankcase should also be provided with a breather valve means adapted to permit escape of air underpressure from the crankcase chamber while preventing loss or throwing of oil.

It is one object of my invention to provide a compressor of the above type having oil trough means mounted in the crankcase within thepath of the usual oil dipper carried by the connecting rod, and a pump for elevating oil from the lower portion of thecrankcase to said trough means, together with a breather valve device adapted to retain oil vapor within the crankcase while permitting discharge therefrom of air under pressure.

Another object of the invention is to provide an improved splash lubricated compressor having a constantly replenished oil trough or tray removably mounted within the crankcase and adapted to receive oil clippers carried by the connecting rods or crankshaft.

A further object of my invention is to provide, in a compressor of the class just described, a crankcase breather 'device through which the crankcase chamber communicates with the atmosphere, and which comprises a casing having a valve controlled tortuous passage adapted to effect precipitation and return to theoil supply of most of the oil vapors carried in the air about to be expelled from the crankcase, thereby minimizing oil throwing while the compressor is operating.

Other objects and advantages of the invention willappear, in the following description'thereof,

taken in connection with the accompanying drawings, wherein:

V Fig. 1' is an elevational view, partly in section, of an air compressor constructed in accordance witlithe invention Fig. 2 is a fragmentary sectional view taken on I the line 22 of Fig. 1;

Fig. 3 is a fragmentary sectional view taken on'the'line 33 of Fig. 1;

' Fig. 4 is an elevational side view of the compressor showing a section thereof taken on the line 4+4? of :Fig. Land Fig-.5 is a sectional view taken on the line 5,-5 of Fig. 41 7 Referring to'Fig. 1 of the: drawings, there is provided a fluid compressor ID comprising a crankcase H adapted to be mounted on a suitable support, a cylinder casing l2 mounted on the crankcase-and a head l3 secured to the cylinder casing. Formed in the crankcase H is a crankcase chamber i5 within which is disposed a crankshaft it having one end I! thereof journaled in a roller bearing assembly l8 and the other end I9 journale'd in a roller bearing assembly 20, both of; which bearing assemblies are mounted insuitable recesses formed in the crankcase ll. The end IQ of the crankshaft is adapted to be operatively connected to a suitable drivingmotor, not shown, and extends outwardly of the crankcase through a bore formed in an end bearing coverZZlwhich is secured to the crankcase 'l I. The crankshaft 16 is operatively connected, by meansof connecting rods 23 and 2d journaled thereon, to-a pair of fluid compressing pistons not shown-which are suitably. mounted within the cylinder portion l2 of the compressor. U V

The compressor i0 is provided. with a splash lubricating system by means of which fluid lubricant isconveyed from-a supply contained in the lower portionof the crankcase chamber l5 to the bearings and pistons of the compressor. According to the'invention, a lubricant tray 25 is disposed in the crankcase chamber l5 between the crankshaft lfiand the portion of the crankcase containing the lubricant supply, which tray may-be integrally cast or otherwise formed of a suitable material such as-aluminum, and is pro-3 videdwith -a flange 26 secured by means of bolts 28 00 aninte'rior lug ortion 2910f the crankcase ll. Asshown in'Figs. 1 and 2 of the drawings, 7

the lubricant tray. 25-f-urther comprises a trough portion 3i formed 'adjac'ent the flange 26' and adapted to be disposed beneatl-i 'the' connecting rod 24, and a similar trough-portion 33 adapted to be positioned under the connecting rod 23, which trough portions communicate with upwardly inclined channel portions 34 and 35, respectively, terminating in an elevated end portion 36 which is adapted to abut a wall 37 of the crankcase H. Suitable bores are formed in the end portion 36 of the tray for receiving the ends of a pair of hollow dowels or conduits 4!] and M, which are secured in the wall 31 and provide communication to the channels 34 and 35, respectively, from a lubricant well 43 formed in the crankcase H.

As shown in Figs. 1 and 4, the channel portions 3! and 33 of the lubricant tray 25 are disposed at right angles with respect to the axis of revolution of the crankshaft l6, and are adapted to receive lubricant dippers 45 and 46 carried by the respective connecting rods 24 and 23, through the medium of which fluid lubricant contained in the trough portions may be impelled to the various portions of the compressor requiring lubrication.

For elevating lubricant from the supply contained in the lower portion of the crankcase chamber l5 to the lubricant well 43 feeding the trough portions 31' and 33, there is provided lubricant pump means comprising a gear case 53 secured to the crankcase ll adjacent the end I! of the crankshaft and having formed therein two connected circular chambers 55 and 52 in which are mounted interengaging lubricant conveying gears 53 and 54, respectively, each of which is journalcd on one of a pair of boss portions 55 formed on the gear case. The upper gear 53 is concentrically aligned with the bearing end I! of the crankshaft l6 and is operatively secured thereto by means of pins 51. The gear 54 is adapted to be operated through the medium of the gear 53 and crankshaft IE to draw fluid lubricant from the supply contained in the crankcase chamber l5 through a passage 59 to the chamber 52 and to elevate the lubricant to either of a pair of dischargeports 60, depending on the direction of operation, through which the lubricant flows to the lubricant well 43.

In order to prevent undesired lubricant throwing by operation of the splash lubrication means just described, the compressor I9 is provided with a crankcase breather device, which is illustrated in Figs. 4 and 5 of the drawings and comprises a casing 65 which is disposed within the crankcase chamber I5 and is secured by suitable means such as bolts 66 to a side cover 61, which in turn is secured to the crankcase II by bolts 68. The casing 65 of the breather device has a tubular hood portion 10 which extends into the crankcase chamber 15 below the crankshaft IE but beyond the path of movement thereof, and which is provided with a downwardly directed opening ll communicating with a chamber 12 formed within the casing 65. As is best shown in Fig. 5, the casing 65 is provided with interior bafiies 14 providing a tortuous passage from the hood portion 70 through the chamber t2, the upper end of which communicates by way of a valve chamber 15 formed in the casing with a passage 16 leading to the atmosphere. A ball check valve 1'! is disposed in the valve chamber l5 for preventing back flow of atmospheric air from the valve chamber to the chamber 72 within the casing 65 of the breather device. A plug member 18 having screw threaded engagement in a suitable bore formed in the casing 65 is provided for limiting movement of the check valve 11 away from its seat.

When the crankshaft I 6 of the compressor I0 is rotated in the usual manner, the gears 53 and 54 of the lubricant pump are operated to supply lubricant from the crankcase chamber l5 to the well 43, from which lubricant is free to flow through the conduit 4| and channel 35 to the trough portion 33 of the lubricant tray 25, and also by way of the conduit 40 and channel 34 to the trough portion 3|. From the trough portions 3! and 33 of the tray the lubricant is thrown to the various operating parts of the compressor by means of the dippers 45 and 46 carried by the connecting rods.

Meanwhile, air trapped within the crankcase chamber l5 and subjected to pressure upon downward or suction strokes of the two compressor pistons is caused to flow through the opening it in the hood portion 13 of the casing 65 and thence past the baffles l4 within the chamber 72 and the check valve TI to the valve chamber "l5 and atmospheric passage 16. It will thus be seen that by reason of the protection afiorded the opening H by the hood portion 10 extending into the crankcase chamber E5, the admission to the breather device 65 of lubricant spray or vapor produced by operation of the splash lubricating means as just described is minimized, and that any remaining lubricant vapor passing with air under pressure through the tortuous passage provided in the chamber 12 of the breather device will be largely condensed and returned to the crankcase chamber before the air is discharged to the atmosphere.

From the foregoing it will be apparent that,

according to my invention, a fluid compressor 1 may be provided with an improved form of splash lubrication means comprising an elevated lubricant tray for maintaining a proper quantity of lubricant within reach of the usual dipper means carried by the crankshaft, pump means for supplying lubricant to said tray, and crankcase breather means operative to prevent lubricant spray or vapor from being discharged from the crankcase while permitting air under pressure to escape therefrom to avoid build up of back pressure within the crankcase.

While one illustrative embodiment of the invention has been described in detail, it is not my intention to limit its scope to that embodiment or otherwise than by the terms of the appended claims.

Having now described my invention, what I claim as new and desire to secure by Letters Patent, is:

1.111 a compressor of the type adapted for splash lubrication and including a crankcase having a lubricant supply passage, a crankshaft and lubricant dipper means carried thereby, in combination, a lubricant tray member adapted to be mounted. within said crankcase and having an apertured elevated channel portion and a trough portion communicating therewith, hollow dowel means secured to the crankcase and adapted to lit in the aperture in said elevated channel portion for providing communication through which lubricant can flow from said supply passage to said trough portion, and means for removably securing said tray in a position in which said trough portion is aligned within the path of movement of said dipper means.

2. In a compressorof the type adapted for splash lubrication and including a crankcase having a lubricant supply passage, a crankshaft and lubricant dipper means carried thereby, in combination: an apertured lug portion formed on an interior wall of said crankcase; a plurality of projecting dowel elements having the ends thereof secured in another wall of said crankcase and constituting conduits communieating with said lubricant supply passage; a lubricant tray comprising elevated channel portions having inlet apertures adapted for engagement with the respective projecting ends of said dowel elements, a plurality of trough portions having gravity flow communication with said channel portions and an apertured flange portion spaced from said channel portions; and bolts adapted to be fitted in the apertures in said lug portion and said flange portion for removably securing the tray in a position in which said trough portions are aligned with the paths of movement of said dipper means.

3. In a compressor of the type adapted for splash lubrication and including a crankcase having a lubricant supply passage, a crankshaft and lubricant diper means carried thereby, in combination: means forming a lubricant well on a Wall of said crankcase above the normal line of lubricant in said crankcase, pump means attached to said crankcase wall for velevating lubricant from the crankcase to said well, a lubricant tray comprising a plurality of trough portions into which said dipper means are adapted to dip,

and means for removably attaching said lubriu cant tray to said first means and to a wall of CLYDE C. FARMER. 

